Self-freeing ice tray



Dec. 29, 19-36. 0. B. KNIGHT SELF FREEZING ICE ThAY Filed April 16, 1931 2 Sheets-Sheet 1 IN V EN TOR.

A TTORNEY Dec. 29, 1936. D B KN|GHT 2,066,042

SELF FREEZING ICE TRAY Filed April 16, 1931 2 Sheets-Sheet 2 29 INVENTOR.

- Donald B. Kniqhr.

A TTORNEY Patented Dec. 29, 1936 UNITED STATES SELF-FREEING ICE TRAY Donald Branch Knight, Brooklyn, N. Y., assignor,

by mesne assignments, to General Motors Corporation, a corporation of Delaware Application April 16, 1931, Serial No. 530,501

21 Claims. -(c1. 62108.5)

This invention relates to trays adapted to be inserted in evaporators or cooling elements of household mechanical refrigerators for containing foods and desserts to be congealed or water and other liquids to be frozen.

A considerable problem is presented in the re moval of trays after the freezing operation has been accomplished on account of their sticking to the shelves or other supporting surfaces.

It is an object of the invention to provide in conjunction with an ice tray a device for automatically freeing the tray from the bottom and sides of the ice freezing compartment in which the tray is placed to freeze its contents.

Further objects and advantages will be apparent from the'following description taken in con- .nection with the accompanying drawings, where- Fig. 1 is a fragmentary, front elevation illustrating one application of the invention;

Fig. 2, a fragmentary, longitudinal section taken on the line 22 of Fig. 1;

Fig. 3, a similar view with the parts in the position they assume after freezing;

Fig. 4,a fragmentary, longitudinal section of a modified form; Fig. 5, a similar view with the parts in the position they assume after freezing;

Fig. ,6, a fragmentary, longitudinal section of another modified form';

Fig. '7, a fragmentary, longitudinal section of a further modified form; h

Fig. 8, a fragmentary bottom plan view taken on the line 88 of Fig. '1; Fig. 9, a fragmentary, longitudinal section of a still further modified form; and

Fig. 10, a fragmentary bottom plan view of the tray of Fig. 9. I

Referring to the drawings, an evaporator I0 or freezing element of any desired construction is provided with a number of compartments l l formed by the sides of the evaporator, and shelves I2; The compartments l I are of a size toaccommodate ice trays l3 capableo'f holdingwater or other substances, such ice trays being formed of any desired material and having handgrips It by means of which they may be removed. Water or other liquid spilled over the sides of the tray when inserting in the evaporator will freeze, as 5 well as moisture condensed 'upon the exterior of the trays, and cause the trays to stick tight so that considerable difficulty is encountered in removing them. In order to cause the trays to free themselves after their contents become frozen, a 55 bellows Ii filled with water is placed under the front end of the tray or handgrips It. On .account of the fact that the front end of the tray is the last to freeze the water in the bellows is the last to congeal and the resulting expansion will lift the front end 'of the tray from the shelf 5 I2 as shown in Fig. 3, after which the tray may be readily removed.

In lieu of the construction just described the construction shown in Figs. 4 and 5 may be employed. With this construction an ice tray I6 10 of slightly modified form is provided with a recess I1 for the accommodation 'of an expansible vessel 18 adapted to contain water or other liquid which will expand upon freezing'and lift the ice tray free, breaking the ice which is frozen around 15 it so that the tray may be easily removed. The invention not only contemplates expansible members such as those illustrated,but other desirable applications of the invention will be apparent. For example, in Fig. 6 there is shown an ice tray 20 I9 provided with a depression in its under side formed by the bulged up or elevated portion 20, and with a diaphragm 2| forming a chamber 22 adapted to contain water or other freezable substance. At its center the disk 2| is provided with 25 a shelf engaging fulcrum or boss 23 adapted{ when the liquid in the compartment 22 freezes,

to raise the front edge of the tray from the shelf.

In Fig. 'l is illustrated a further modified construction which comprises a tray 24 having its '39 front extremity turned downwardly and rearwardly and forming upper and lower horizontal ledges between which is-disposed a bellows 25. The expansion of the bellows 25 will lift the front end of the tray as in the previously discussed 35 embodiments of the invention. To the downwardly turned front end'of the tray is attached by means of bolts or other fastening means, a handle 26. In Figs. 9 and 10 is shown a modification similar'to that of Figs. 4 and 5, except'40 that the tray 21 is not only provided with an elevated portion '28 in its front; biit'the front is also bent over and has -attached thereto a handle Y 29, a rearwardiy extending ledge fifl' joining thehandle with the under surface 0f "the elevated"45 portion 28. In-this construction the bellows is-" carried byfthe individual tray'front instead" by the tray proper. The'expansible diaphragm comprises upper and lower cup members 3'lfa 32, the'l'owe'r-cup member 32 having 'a2's'helfcontacting knob 33 which rests upon the shelf l2. The bellows l5, I8 and 25 are provided with removable plugs 34, 35 and 36 by means of which the bellows may be filled.

-It will be obvious to those skilledin the art hat various other changes may be made, in the nstruction and arrangement without departing from the spirit of the invention and therefore the invention is not limited to what is shown in the drawings and described in the specification, but only as indicated in the appended claims.

I claim: I.

1. In combinationwith an ice tray, an expansible member containing a substance which expands upon freezing for breaking the tray entirely free from a supporting shelf after the major portion of the substance in the tray has been frozen.

2. In combination, an ice tray, a support for said tray, and a freezing-water thermostat adapted to move said tray relative to its support.

3. In combination with a tray-having a han-' dle, a support for said tray, and a freezing-water thermostat constructed to exert a force between the handle and the support for lifting the tray from the support.

4. In apparatus of the class described, a tray, and a device adapted to exert force against said tray for automatically moving said tray from its 7 support comprising anexpansible element containing a substance which expands upon freezing.

5. In combination with a tray for receiving substance to be chilled, a member adapted to expand upon freezing connected to the exterior of the tray in a manner tolift a portion of the tray from a support upon freezing of the expansible member.

6. In combination with a tray for receiving matter to. be chilled, a liquid-containing expansible member connected to the exterior of the tray ina manner to lift a portion of the tray from a support upon freezing of the liquid within the expansible member.

7. In combination, a tray having an indented portion, a support for thetray, and an expansible member within said indented portion for exerting pressure between the tray and its support.

8. In combination, a tray having an indented portion, a support for the tray, and an expansible member within said indented portion for exert-,'

ing pressure betweenthe tray and its support operable upon freezing.

9. In combination, a tray having an indented portion, a supportfor said tray, and a freezing thermostatic member within said indented portion for moving the tray relative to its support.

10. In combination, a tray having an indented portion, a front plate for said tray, a support for said tray, and a freezing thermostatic member within saidindented portion and attached to said front plate for exerting pressure between the tray and its support.

, 11. In combination, a tray having a depression in the bottom, a support for the tray,,a flexible member covering said depression and forming a'fluid-tight chamber, a portion of said flexible member engaging said support, and matter with- -in said chamber which expands upon freezing,

whereby the tray will be lifted from its support upon the freezing of the expansible matter.

12. In combination with an ice tray having a recess on its under side, a bellows in said recess, and a substance within said bellows adapted to expand the bellows upon being changed from a fluid to a solid.

13. An evaporator for a refrigerator including a support, a tray adapted to contain matter to be changed by transfer of heat relative thereto when resting on said support, and an expansible member constructed to-urge said support and tray apart upon the transfer of heat.

14. A cooling device comprising, in combination, a cooling element, a shelf supported by the element, a slidable container supportedby the shelf, and a temperature responsive motor for breaking an ice bond between the container and the shelf.

15. A cooling device comprising, in combination, a cooling element, a shelf supported by the element, a slidable container supported by the shelf, and a temperature responsive bellows containing a freezing solution operatively connected to said container for moving at least a portion of .tion, a cooling element having a support formed thereon, a receptacle adapted to contain a substance to be congealed orfrozen associated with the support of the cooling element, and temperature responsive means including an element carried by said receptacle and movable relative thereto for moving at least a portion of said receptacle relative to said support.

18. An ice tray having a contact surface for engagement with a cooling element and means outside the contact surface to automatically exert force between the'tray and said element angularly to said surface to-release an ice bond between the surface and the element.

19. An ice tray having a contact surface for engagement with a cooling element and means outside the contact surface and responsive to decrease of temperature to automatically exert force between the tray and said element angularly to said surface to release an ice bond between the surface and the element.

20. An ice tray having a contact surface for engagement with a cooling element and a device which changes its volume when affected by heat to automatically exert force between the tray and said element angularly to said surface to release an ice bond between the surface and the element.

21. An ice tray having a contact surface for engagement with a cooling element and a member outside the contact surface and actuated by expansion of a freezing substance other than substance contained in the tray to automatically 

